Add folder anatomy (scripts/agent.py + references/api-reference.md) for 648 cybersecurity skills

Complete skill folder anatomy across all cybersecurity skills:
- scripts/agent.py: 80-150 line Python agents using real libraries (impacket,
  boto3, azure-mgmt-*, kubernetes, pefile, yara, scapy, shodan, stix2, etc.)
- references/api-reference.md: real API documentation with method signatures
- LICENSE: MIT license for all skill folders

skills/exploiting-template-injection-vulnerabilities/references/api-reference.md

@@ -0,0 +1,55 @@
+# API Reference: SSTI Detection Agent
+
+## Dependencies
+
+| Library | Version | Purpose |
+|---------|---------|---------|
+| requests | >=2.28 | HTTP client for sending template injection payloads |
+
+## CLI Usage
+
+```bash
+python scripts/agent.py --url "https://target.com/page" --param name --method GET --output ssti.json
+```
+
+## Functions
+
+### `test_ssti_detection(url, param, method, headers) -> list`
+Tests 7 engine-specific payloads (`{{7*7}}`, `${7*7}`, etc.) and checks if `49` appears in the response.
+
+### `identify_engine(url, param, method, headers) -> dict`
+Differentiates engines: `{{7*'7'}}` returning `7777777` = Jinja2, `49` = Twig. Also tests Freemarker (`${.now}`) and Velocity.
+
+### `test_jinja2_rce(url, param, method, headers) -> list`
+Tests `cycler.__init__.__globals__.os.popen`, `lipsum.__globals__`, and `config.SECRET_KEY` disclosure.
+
+### `test_twig_rce(url, param, method, headers) -> list`
+Tests `filter('system')` and `file_excerpt` payloads.
+
+### `test_freemarker_rce(url, param, method, headers) -> list`
+Tests `freemarker.template.utility.Execute` for Java command execution.
+
+### `run_assessment(url, param, method) -> dict`
+Runs detection, identifies engine, then tests engine-specific RCE payloads.
+
+## Detection Payloads
+
+| Engine | Payload | Expected |
+|--------|---------|----------|
+| Jinja2/Twig | `{{7*7}}` | `49` |
+| Freemarker | `${7*7}` | `49` |
+| ERB/EJS | `<%= 7*7 %>` | `49` |
+| Smarty | `{7*7}` | `49` |
+| Velocity | `#set($x=7*7)$x` | `49` |
+
+## Output Schema
+
+```json
+{
+  "target": "https://target.com/page",
+  "parameter": "name",
+  "vulnerable": true,
+  "engine": {"engine": "Jinja2", "language": "Python"},
+  "rce_tests": [{"name": "cycler_popen", "rce_confirmed": true}]
+}
+```